Model-free estimation of a psychometric function


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[b,lims] = binom_lims(r,m,x,gl,link,p,K,initval )

Maximum likelihood estimates of the parameters of the psychometric function with guessing and lapsing rates, only guessing rate, or only lapsing rate.


r: number of successes at points x

m: number of trials at points x

x: stimulus levels

Optional input:

gl: indicator, calculate only guessing if 'guessing', only lapsing if 'lapsing' and both guessing and lapsing if 'both'; default is 'both'  

link: name of the link function; default is 'logit'

p: degree of the polynomial; default is 1

K: power parameter for Weibull and reverse Weibull link; default is 2

initval: initial value for 'guessing' and 'lapsing'; default is [0.01 0.01] if guessing and lapsing rates are estimated and 0.01 if only guessing rate or only lapsing rate is estimated


b: estimated coefficients for the linear part

guessing: estimated guessing rate

lapsing: estimated lapsing rate

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